Fiber-board box



Patented Oct. 21, 1924.,

j 11' i "i ES JOHN W. WEBB, OF CHICAGO, ILLINOIS.

FIBER-BOARD BOX.

No Drawing.

To all whom it may concern:

Be it known that I, JOHN W. WEBB, a

.citizen of theUnited States, residing at Chiboard is subject to the softening effectof moisture, as for use in cold storage, ocean or other transportation by water, storage in basements, shipment or storage under circumstances when exposure to inclement weather is liable to occur, and for use for the reception of articles which contain or attract moisture as the shipment of fresh fruits or hygroscopic substances. Moreover when boxes constructed of such materials and filled with heavy contents are shipped or stored in quantity, stacked up several boxes high, especially when the contents are of a soft and yielding nature, the boxes are liable to crumple, or to burst, either sidewise, causing the pile to topple over, or at the bottom, crushing and often ruining such boxes as may lie below. Applications of parafiines and other waxes have been proposed and tried for waterproofing the paper and counteracting the effects of moisture. but are open to the objections that because of the smooth and unctious nature of the substance the boxes cannot be effectually sealed with the adhesives commonly used, as silicate of soda and glue, and that the effect of heat so softens the materials mentioned that under ordinary summer temper atures practically no stiffening or strengthening effect can be derived from them. The object of my invention is the provision of means for so strengthening and stiffening paper board that boxes may be constructed in the manner now universally practiced which shall be free from the objections above mentioned and thus such boxes may be used under conditions and for purposes for which paper boxes as heretofore constructed have not been adapted. To this end I have devised and invented a novel method of strengthening and stiffening Application filed October 12, 1922. Serial No. 594,187.

boxes made of fibrous paper board and thereby produced, as a new article of manufacture, the novel paper board hereinafter described, the essential elements of my invention being more particularly pointed out in the appended claims.

My invention is based on the discovery, made by me, that the desired qualities above adverted to can be imparted to fiber board or corrugated paper board by impregnating it with melted sulphur which, when cooled, will form a skeleton or network of solidified sulphur strengthening and stiffening it as Well as waterproofing it without impairing its capacity for being sealed by the ordinary adhesives mentioned.

The sulphur may be applied in any one of several different ways. Preferably I employ ordinary crude sulphur, melted. and the fiber board or corrugated paper board boxes are impregnated by dipping them in the melted bath. The melted sulphur will at once permeate the outer portions of the fibrous material, and when the article is withdrawn the adherent melted sulphur will quickly be absorbed by capillary action, leaving any printing which the box may bear unaffected and changing the natural color of the fiber but very slightly. The ordinary adhesives by means of which the cover flaps of the boxes are sealed will adhere to the surface of the treated box as firmly as before the application of the sulphur. Any surplus of sulphur on the surface of the box may be removed by treating the box in an oven sufficiently hot'to liquefy the sulphur and permit its complete absorption, or by exposing it to radiant heat of sufficiently high temperature. The quantity of sulphur applied should not be excessive, but only such amount as to permit complete absorption.

Another procedure which I may follow in practicing my invention consists in coating the boxes as thoroughly as possible with dry cold powderedsulphur, or sulphur reduced to a thin paste, and then subjecting the box to heat treatment to melt the sulphur so that it will permeate the material.

Still another means of applying the sulphur to the surfa'e of the boxes or other paper articles to be treated consists in form ing a compound of powdered sulphur suspended in a volatile liquid vehicle, as gasoline, benzol, benzine, or naphtha,in which if desired, a small proportion of rubber may be dissolved,and either coating the box with the compound by a brush or by dipping and thenevaporating the liquid and heating the article to liquefy the sulphur and cause it to permeate the fibers.

Treated as above described, the strength of the fiber is not impaired and the boxes are rendered much more stifi and rigid, and this increase in strength is retained under the conditions of dampness before men-- tioned which affect so injuriously the strength of paper board boxes not so treated.

The most extreme hot Weather temperature is of course wholly insufficient to impair the strength imparted by the treatment in the sli htest degree.

Vhile the solidified network or skeleton of solidified sulphur contained in the pores of the treated box is practically odorless it has in some measure a preservative effect and is repellent to insects and vermin, so

that its efiects in this respect are beneficial.

Although I prefer to coat the boxes after they have been constructed for the reason that maximum strength is attained in this manner, the paper board may be treated as above described and the boxes constructed JQHN W. WEBB. 

